In recent years, a type of mobile communications network known as an “ad-hoc” network has been developed. In this type of network, each mobile node is capable of operating as a base station or router for the other mobile nodes, thus eliminating the need for a fixed infrastructure of base stations. As can be appreciated by one skilled in the art, network nodes transmit and receive data packet communications in a multiplexed format, such as time-division multiple access (TDMA) format, code-division multiple access (CDMA) format, or frequency-division multiple access (FDMA) format.
More sophisticated ad-hoc networks are also being developed which, in addition to enabling mobile nodes to communicate with each other as in a conventional ad-hoc network, further enable the mobile nodes to access a fixed network and thus communicate with other mobile nodes, such as those on the public switched telephone network (PSTN), and on other networks such as the Internet. Details of these advanced types of ad-hoc networks are described in United States Patent Application Publication number US-2002-0058502-A1 entitled “Ad Hoc Peer-to-Peer Mobile Radio Access System Interfaced to the PSTN and Cellular Networks”, filed on Jun. 29, 2001, in U.S. Pat. No. 6,807,165 entitled “Time Division Protocol for an Ad-Hoc, Peer-to-Peer Radio Network Having Coordinating Channel Access to Shared Parallel Data Channels with Separate Reservation Channel”, granted Oct. 19, 2004, and in U.S. Pat. No. 6,873,839 entitled “Prioritized-Routing for an Ad-Hoc, Peer-to-Peer, Mobile Radio Access System”, granted Mar. 29, 2005, the entire content of each being incorporated herein by reference.
As can be appreciated by one skilled in the art, it is desirable to monitor the movement of nodes in a multihopping network in order to, for example, manage the links between nodes, perform location measurement operations, and so on. An example of a system and method for determining the mobility of a node in a network is described in U.S. Pat. No. 7,181,214 entitled “A System and Method for Determining the Measure of Mobility of a Subscriber Device in an Ad-Hoc Wireless Network with Fixed Wireless Routers and Wide Area Network (WAN) Access Point”, granted on Feb. 20, 2007, the entire contents being incorporated herein by reference. Further examples of techniques for determining mobility are set forth in United States Patent Application Number 20020160764, and in U.S. Pat. Nos. 6,795,688 and 6,075,797.
Other techniques for detecting the mobility of a node are based on the assumption that a significant number of neighboring nodes are stationary by nature. This assumption is limiting because it assumes a presence of inherently stationary nodes, and it does not address the issue of a large presence of inherently mobile nodes that are for a time stationary but have the potential to move, which can lead to network instability.
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